Twin Stars is a solitaire game system, one that Button Shy has slowly been releasing as bonus items. Each play consists of two characters and one scenario. However, you can mix and match the characters, as well as adjust the difficulty so there is a lot variety going on.
I've only played the first one, Escape from the Brig, which I am sure is also the simplest one. It's essentially a race against time. Can you get your pawn to end of its track before the guard pawn gets to the end of its track?
At the end of the day, the game is all about dice manipulation. Each character has a space for each pip, with either symbols or an effect. Roll the die and assign one to each character. If they form a combination of symbols listed on the scenario card, perform that action and start over. Otherwise, drop one die by one pip and reroll the other then check for combinations.
I'll be honest. The game system is more complex than you'd really expect for three cards, two dice and some tokens. The process of completing a turn can take several steps. I'm not actually saying Twin Stars is complex. Just that I was expecting a a very simple roll-and-react game and there's an actual procedure with choices, although bad rolls can still sink you.
I am going to continue to be honest. I'm really not one for solitaire games, although I realize I have played quite a few over the years. When I do play one, I wanted to be something that is easy to set up and that will play fairly quickly. Because, quite frankly, it tends to be an act of fidgeting for me.
So, three cards, some tokens and a couple of dice works for me. Heck, if I feel like it, I can randomly deal out the characters in the scenarios.
I will have to see the other scenarios in the other characters and see how truly flexible the system is, as well as how interesting it is in the long run. But, for three dollars to get the PDF files, it's an investment that I feel comfortable with.